52 AUSTKALIA1T MALACOSTBACA. 



Genus Psextdocaecikts, Milne-Edwards. 

 Carapace slightly convex and a little embossed near the front. 

 Front nearly horizontal. Antero-lateral borders moderately 

 curved and armed with more or less prominent teeth ; postero- 

 lateral borders straight, convergent. Basal joint of the external 

 antennae very small, second joint scarcely reaching the front, 

 third joint occupying, but not filling, the orbital hiatus. Palate 

 not canaliculated. Chelipedes very large. 



83. Pseudooareinus gigas. 



Cancer gigas, Lam., Hist, des Ani. Sans Vert., t. v., p. 272. 

 Pseudocarcinus gigas, Milne-Edwards, Hist. Nat. Crust., i., 

 p. 409. 



Carapace slightly convex and swollen on the sides ; front 

 armed with four thick pointed teeth, near the base of which on 

 the gastric region is an equal number of rounded tubercles. 

 Antero-lateral borders obscurely divided into four lobes, each 

 armed with two or three spinif orm teeth. Orbits divided by four 

 fissures. Anterior legs very thick, posterior border of the arm 

 spinose ; carpus armed internally with two teeth. Ambulatory 

 legs rounded, armed with spines on the upper border of the 

 third joint. [M.-Udte.] 



Bass' Straits; Port Philip. 



This species is one of the giants of the class, the carapace 

 being sometimes two feet in breadth. 



G-enus MEDiEUs, Dana. 

 Carapace narrow, scarcely transverse, naked; front rather 

 short. Orbits with two teeth below and one externally. 

 Antero-lateral margin produced under the orbit. Anterior legs 

 thick. 



84. Medseus nodosus. A.M. 



Medceus nodosus, A. M.-Edw., Nouv. Arch, du Mus., t. ix., 

 p. 212, pi. viii., fig. 2. 



Carapace strongly lobulated, the lobules granular. Front 

 slightly emarginate in the middle, straight and prominent. 

 Antero-lateral borders divided into four rounded and granular 

 teeth, of which the two posterior are the strongest. Anterior 



